1. Field of the Invention
The present invention relates to a color variation inducing device, and more particularly to such device capable, under application of a low voltage, of inducing color variation in a thermally color inducing article bearing a thermochromic layer thereon, by positioning in contact with or in the proximity of said article or by action through air blowing means.
2. Related Background Art
As means for inducing color variation in a thermally color-varying or thermochromic article, the Japanese Patent Application Laid-open No. 62-101598 proposed a configuration of providing a conductive heat-generating member on the rear face of a thermochromic sheet and inducing a color variation in the image formed on said sheet by electric current heating. Also the Japanese Utility Model Application Laid-open No. 62-139573 proposed a configuration of bringing an electric heating utensil, equipped with a heating resistor such as of tungsten or nickel, into contact with a thermally color varying material formed on the surface of an animal toy or the like, thereby inducing a color variation in thus contacted area.
Although there have been made certain proposals on heating means for inducing color variation in the thermally color-varying layer as cited above, no effective cooling means has been disclosed for inducing color variation by cooling in thermally color-varying layer, and the color variation by cooling has had to be achieved by a cooling medium such as cold water or ice pieces, or by keeping the thermally color varying article in a refrigerator for utilizing the cold air therein.
Such cooling means may be applicable in certain specified places such as in home, but are unable to immediately induce color variation in the thermochromic layer of the article whenever necessary regardless of the place, so that the function of the thermally color-varying article having a color varying point in a low temperature range could not be effectively exploited.
Also the above-mentioned cooling media, being limited in duration of coldness, require a cumbersome preparatory operation each time. Furthermore, the thermally color-varying articles not resistant to water are often deteriorated by dews, waterdrops or leaking water, not only in the direct contact of said cooling medium but also in the indirect contact with a container holding said cooling medium therein.